Answer:
- 18y = 1
Step-by-step explanation:
Adding the 2 equations term by term on both sides gives
(- 5x + 5x) + (- 9y - 9y) = (3 - 2), that is
0 + (- 18y) = 1
- 18y = 1
The sum of the terms of a geometric sequence with common ratio lesser than 1 is calculated through the equation,
Sn = (a1) x (1 - r^n) / (1 - r)
Substituting the known values,
S5 = (6) x (1 - (1/3)^5) / (1 - 1/3) = 242/27
Thus, the sum of the first five terms is approximately equal to 8.96.
It seems most likely that ...
... Samantha will save $37.50 because she must first find the 25% sale price before taking the extra 50% reduction
_____
In the real world, it seems probable that Samantha will be offered the choice of using the coupon <em>or</em> the sale discount. If she chooses tht 50% coupon, her savings will be $30. If she chooses the marked sale discount, her savings will be $15.
The scenario above assumes she gets 50% off the sale price of $45, so saves $15+22.50 = $37.50 off the original price.